Twice a month through September, the Ohio Department of Transportation is conducting free hard hat tours of the George Voinovich Bridge construction area. Tours are rain or shine, although if the weather becomes overly inclement, the event will be cancelled.

Tours are conducted by Trumball-Great Lakes-Ruhlin (TGR), a joint venture between Trumbull Corporation, Great Lakes Construction Company and the Ruhlin Company, which was the successful bidder on the $273 million project that included demolition of the existing 1959 Innerbelt Bridge and the construction of a new, five lane, eastbound structure. The project is slated for completion this fall.

Attendees walk the entire construction site and hear insider details about things such as the steel I-beams that support the concrete pilings, or the "HP18 x 204's," wherein the H indicates the shape, the 18 refers to an 18" measurement on the piling and the 204 indicates 204 pounds-per-foot.

"These piles come in at 90 feet long," said Karen Lenehan, public information consultant for TGLR, during a tour last week. "They're the largest piles manufactured in United States." She adds that the pilings are required to be driven down to bedrock some 200 feet below ground. They must be hammered twenty times with industrial driving equipment in order to move just one inch.

"How do you know when you reach bedrock?" mused Lenehan. "When you hit it twenty times and it doesn't move."

Lenehan also offered comprehensive details on the giant 28- by 28- by 10-foot concrete footers; the prominent concrete columns, which are hollow and include inspection doors; the steel knuckles, tension ties, deltas, bridge bearings and deck girders; and the permanent catwalks that web the area under the deck of the bridge, among other components.

Lenehan also told the tale of how the entire project was nearly held hostage by a pair of mating Peregrine falcons that threatened to delay the demolition of the old bridge. Fortunately, the babies learned to fly ahead of a critical date and vacated the nest.

"We got the okay," recalled Lenehan of getting the thumbs-up from the Ohio Department of Natural Resources when the junior falcons took flight. "We could go ahead with our big explosive demolition on July 12, 2014."

Other softer details of note include a forthcoming fish habitat that will be similar to one that was constructed for the westbound bridge. The protected area is essentially fenced off from the rest of the river by a slotted barrier and is planted with vegetation the fish can eat.

"Fish can swim out of the way of the freighters," said Lenehan. "They can rest; they can feed, and then they can swim back out."

Also included in the project is a protected area for humans - for walking, biking and running. The contract includes extending the southern terminus of the all-purpose trail along Scranton Flats to a point adjacent to Sokolowski's Inn, as well as a new green space for Tremont.

Erin O'Brien's eclectic features and essays have appeared in the New York Times, the Los Angeles Times, the Cleveland Plain Dealer and others. The sixth generation northeast Ohioan is also author of The Irish Hungarian Guide to the Domestic Arts. Visit erinobrien.us for complete profile information.